There should be no need to disconnect the 12 volt battery if a maintainer is used. I'd leave the charge at about 50%, not the low state suggested by the manual. That way if the car needs to warm or cool the battery, it can.

As reported above, the manual states to "discharge the high voltage battery until two or three bars remain on the battery range indicator." Can anyone tell me approximately what SOC this equates to? It sounds very low. Also, can anyone tell me if the car has the ability to turn something on to warm up the battery if it gets too cold - even if it isn't plugged in?

eurosteve wrote:As reported above, the manual states to "discharge the high voltage battery until two or three bars remain on the battery range indicator." Can anyone tell me approximately what SOC this equates to? It sounds very low. Also, can anyone tell me if the car has the ability to turn something on to warm up the battery if it gets too cold - even if it isn't plugged in?

2 or 3 bars would be between 11 and 19 percent SOC.

The car doesn't do any battery conditioning when SOC is less than 30%.

The problem is that the manual doesn't discuss what is the proper long-term winter storage, just what the proper long-term storage is, regardless of outside temperature. Battery conditioning appears to be mostly there to make sure the car is drivable when it's extremely cold or warm. If the car has been sitting all winter, the battery will need to be charged before it can be driven, anyways, and will get conditioned as part of being charged.

Someone on another forum suggested a way to keep the car plugged in for long-ish term storage, but still have battery conditioning available to keep the battery happy and the 12V battery maintained: You edit the electric rate schedule so that off-peak is only available from 2am to 2:15am, and you tell the car it can only charge during that short window. However, over a 5-month period, there's enough cumulative time to fully charge the car. I don't think shortening it to a 5-minute window would help, either.

eurosteve wrote:As reported above, the manual states to "discharge the high voltage battery until two or three bars remain on the battery range indicator." Can anyone tell me approximately what SOC this equates to? It sounds very low. Also, can anyone tell me if the car has the ability to turn something on to warm up the battery if it gets too cold - even if it isn't plugged in?

2 or 3 bars would be between 11 and 19 percent SOC.

The car doesn't do any battery conditioning when SOC is less than 30%.

The problem is that the manual doesn't discuss what is the proper long-term winter storage, just what the proper long-term storage is, regardless of outside temperature. Battery conditioning appears to be mostly there to make sure the car is drivable when it's extremely cold or warm. If the car has been sitting all winter, the battery will need to be charged before it can be driven, anyways, and will get conditioned as part of being charged.

Someone on another forum suggested a way to keep the car plugged in for long-ish term storage, but still have battery conditioning available to keep the battery happy and the 12V battery maintained: You edit the electric rate schedule so that off-peak is only available from 2am to 2:15am, and you tell the car it can only charge during that short window. However, over a 5-month period, there's enough cumulative time to fully charge the car. I don't think shortening it to a 5-minute window would help, either.

I posted that, but I am not sure NOW if it was correct. I have read elsewhere that the battery conditioning is only active when charging is immediate (either charging, or not charging because 'full'). But that actually could have been posted on a Spark EV forum. I don't know which is true. I would love to hear from somebody with a separate meter for charging (or a measuring tool) if battery conditioning happens if delayed charging is configured.

Thanks for all of the help with this. I've posted in an "Ask Chevrolet" thread on another forum to see what they say. Seems unlikely that storage between zero F and 32 F sometimes would be damaging to the battery - as long as the thermal management system doesn't kick in to deplete the battery. But it would be nice to have something definitive from Chevrolet.

eurosteve wrote:Thanks for all of the help with this. I've posted in an "Ask Chevrolet" thread on another forum to see what they say. Seems unlikely that storage between zero F and 32 F sometimes would be damaging to the battery - as long as the thermal management system doesn't kick in to deplete the battery. But it would be nice to have something definitive from Chevrolet.

Since thermal management apparently only works above 30% charge, you need not worry about that happening. It would warm the battery until 30% SOC was reached, then stop.

eurosteve wrote:Thanks for all of the help with this. I've posted in an "Ask Chevrolet" thread on another forum to see what they say. Seems unlikely that storage between zero F and 32 F sometimes would be damaging to the battery - as long as the thermal management system doesn't kick in to deplete the battery. But it would be nice to have something definitive from Chevrolet.

Since thermal management apparently only works above 30% charge, you need not worry about that happening. It would warm the battery until 30% SOC was reached, then stop.

I saw that someone else posted that thermal management only works above 30% SOC (maybe in this thread). Do you know if that's a fact or if this is something that is believed to be true? If this is a fact, then I think I have my answer about the battery running down.